海底矿产资源开发技术经济评价模型研究

海底矿产资源技术经济评价研究是当前我国国际海底资源开发工作中必不可少的重要内容。本文针对海底矿产资源及其开发利用技术现状,基于折现现金流量法,建立了适合我国的海底矿产资源开发技术经济评价模型。并利用该评价模型针对具体项目进行了实例评价分析,结果表明海底矿产资源开发项目具有投资大、收益高、高回报率的特点。进一步的敏感性分析表明:对经济效益影响最大的因素依次为矿石产量、矿石品位和金属价格。     

Study on Preparation of Insensitive and Spherical High Bulk Density Nitroguanidine with Controllable Particle Size

In this study, the solventing‐out recrystallization method was applied to prepare insensitive and spherical high bulk density nitroguanidine (NQ). Experiments were performed at various operating conditions by using N‐methyl‐pyrrolidone (NMP) and acetone as solvent and antisolvent, respectively. The effects of different operating parameters such as NQ/NMP ratio, amount of acetone used, crystallization temperature, stirring speed and stirring time were investigated. The particle size and morphology of the prepared NQ crystals were observed by scanning electron microscopy (SEM), the bulk density was measured by the Archimedes’ method and the impact sensitivity was determined by fall hammer method. The experimental results showed that the solventing‐out recrystallization method could be used to prepare spherical high bulk density NQ with a narrow particle size distribution and the particle size could be controlled by changing the operating conditions. The bulk density of these spherical NQ particles was found to be in the range of 0.94–0.97 g cm⁻³, which is higher than that of needle‐shaped NQ particles, and they became less sensitive towards impact.     

Small‐Scale Safety Testing of Ammonium Nitrate and Mixtures

Ammonium nitrate (AN), gunpowder (GP), and an ammonium nitrate gunpowder mixture (AN/GP) were studied for impact sensitivity by four laboratories using the drop hammer apparatus. Bruceton and Neyer methods were used as experimental protocols and for data reduction. The results are presented as 50 % probability of reaction (DH₅₀). For AN, the DH₅₀ values are widely varied among the participants, from sensitive to completely insensitive (limit of the equipment), with no real correlation among results. GP and the AN/GP mixture exhibited much more sensitivity overall and were in some cases within statistical values extrapolated from previous studies of RDX. The variability in results for the AN data is attributed to the difficulty in determining a positive reaction event for AN, as detailed by Neyer experiments and photography during positive reactions. Variability in results for the GP and AN/GP mixtures is attributed to equipment environment and detection criteria. This work was performed by the Integrated Data Collection Analysis (IDCA) program, a multi‐laboratory effort to standardize safety testing of improvised or homemade explosives funded by the Department of Homeland Security.     

硝化石墨烯诱导CL-20自组装堆垛结构的制备及性能

为改善六硝基六氮杂异伍兹烷（CL-20）的安全性能,用硝化石墨烯（NG）作为结晶诱导剂,通过溶剂-非溶剂法制备了具有自组装堆垛结构的CL-20。采用场发射扫描电子显微镜（SEM）、X射线衍射（XRD）、傅里叶变换红外光谱（FT-IR）、同步热分析仪（DSC-TG）对所制备CL-20的形貌、结构、热性能进行了表征,并对其机械感度进行了测试分析。结果表明,在不同含量NG的诱导下,CL-20重结晶成方形片状晶体,并自组装堆垛成花瓣型、螺型、塔型等结构。在CL-20自组装堆垛结构的形成过程中,NG的诱导作用体现在其片层对CL-20的吸附作用以及其活性基团与CL-20的基团之间形成氢键上。与原料CL-20相比,自组装堆垛结构CL-20热分解温度降低约5 ℃,热分解焓最大提高约33%,质量损失从81%提高到99%,机械感度大幅降低。当NG含量为0.5%时,诱导结晶形成的自组装花瓣结构CL-20的撞击感度最低,为6 J。     

钢筋限制条件下水泥浆体的开裂敏感性研究

为探讨钢筋限制条件下不同配合比水泥浆体的开裂敏感性,测试了水泥浆体的抗拉强度;利用水泥浆体试件轴心处放置的钢筋对浆体所产生的限制收缩作用,连续测试出钢筋的应变值,并计算得到钢筋的应力值.在一定应力范围内,基于钢筋应力与包裹钢筋的水泥石受限收缩应力相等假定,比较了水泥浆体中受限收缩应力与抗拉强度的大小.结果发现,在一定水胶比mW/mB范围内,增加水胶比会降低水泥浆体的开裂敏感性;水胶比相同时,粉煤灰的掺加会显著降低水泥浆体的开裂敏感性.     

Sensitivity and inverse analysis methods for parameter intervals

This paper proposes a sensitivity analysis method for engineering parameters using interval analyses.This method substantially extends the application of interval analysis method.In this scheme,parameter intervals and decision-making target intervals are determined using the interval analysis method.As an example,an inverse analysis method for uncertainty is presented.The intervals of unknown parameters can be obtained by sampling measured data.Even for limited measured data,robust results can also be obtained with the inverse analysis method,which can be intuitively evaluated by the uncertainty expressed in terms of an interval.For complex nonlinear problems,an iteratively optimized inverse analysis model is proposed.In a given set of loose parameter intervals,all the unknown parameter intervals that satisfy the measured information can be obtained by an iteratively optimized inverse analysis model.The influences of measured precisions and the number of parameters on the results of the inverse analysis are evaluated.Finally,the uniqueness of the interval inverse analysis method is discussed.     

超临界流体SAS法制备HMX基传爆药及其表征

采用超临界流体SA S法,通过引入钝化包覆剂FPM2602对超细HM X主体炸药的粒子表面均匀包覆,最终获得超细HM X基传爆药。利用扫描电子显微镜(SEM)表征了原料和超细HM X基传爆药的表面形貌。测定了其撞击感度、冲击波感度及起爆感度,并与J0-9C(I型)传爆药进行对比。结果表明,超细HM X基传爆药的表面形貌得到了明显改善;与J0-9C(I型)传爆药相比,其H50值升高了17.1 cm,冲击波隔板厚度(xR)减小了2.2mm,起爆性能得到了显著提高。     

HTPB推进剂危险性实验研究

依据联合国危险品分级方法,探讨了热刺激、机械刺激和冲击波刺激对低燃速HTPB推进剂、高燃速HTPB推进剂和四组元HTPB推进剂危险性的影响。结果表明,3种HTPB推进剂的热安定性良好,但对火焰热刺激均十分敏感,具有爆燃性;高燃速HTPB推进剂对机械刺激也极其敏感,摩擦感度(p)为96%,撞击感度特性(H50)为37.2 cm。在无约束条件下,3种HTPB推进剂裸药柱对雷管爆轰作用不敏感,而在钢管的强约束条件下,四组元HTPB推进剂对爆轰冲击波作用敏感,隔板值大于18mm。     

EMS测试系统中的主要设备选型

结合标准和实际测试对EMS测试设备的要求,分别对射频电磁场辐射抗抗度和传导骚扰抗扰度测试系统的主要设备技术指标要求和选型,进行了详细阐述和分析,为如何选择满足用户要求的测试系统提供参考。     

光栅辅助的表面波传感器研究

采用严格耦合波方法研究了普通棱镜耦合的表面波传感器与光栅辅助的表面波传感器的传感特性。设计了工作在1550nm处的一维光子晶体与光栅的材料参数与结构参数。光栅的深度为20nm,周期为524.6nm,占空比为0.5。模拟计算表明,光栅的引入导致双共振峰的出现,表面波的模式出现分裂。当外界折射率变化时,两个共振峰向相反的方向移动。利用双共振峰的这种特性进行传感,可以使光栅辅助的表面波传感器的角度灵敏度提高到普通棱镜结构的表面波传感器的3倍以上。